低轨卫星通信网络具有流量分布不均、地面站分布不均且网络负载随时间变化等特点。卫星与就近地面站间的数据传输将会导致空间段动态漏斗型拥塞，进而引发馈线拥塞并劣化端到端通信指标。提出基于区域分流的多径搜索负载均衡路由算法（regional-traffic-detour multipath search load balancing routing algorithm，RMLBR），RMLBR根据卫星网络状态及目的节点距离计算转移概率，以实现区域分流，并以时延为约束进行多径搜索获得最佳路径及备选路径以缓解动态漏斗型拥塞。仿真结果表明，与交通灯智能路由策略（traffic-light based intelligent routing strategy，TLR）和显式负载均衡算法（explicit load balancing，ELB）相比，RMLBR可以有效地缓解漏斗型拥塞，降低端到端延时延及丢包率，并缩小高流量区域范围。
The LEO (low earth orbit) satellite communication networks are characterized by non-uniform traffic distribution, unevenly ground station distribution, and time-varying network load. The data transmission between satellites and the nearby ground stations may lead to dynamic funnel-type congestion in the space segment. It will result in the congestion of the feeder link congestion and the worse end-to-end characteristics. In this article, a regional-traffic-detour multipath search load balancing routing algorithm (RMLBR) is proposed. RMLBR calculates the transition probability according to satellite network status and the source-to-destination distance to implement the regional-traffic-detouring. Under the constraint of path delay, the optimal path and alternative path are obtained by the multipath search to alleviate the dynamic funnel-type congestion. The simulation shows that RMLBR can alleviate the funnel-type congestion, reduce the end-to-end delay, the packet loss, and the size of the high flow area compared with TLR(traffic-light based intelligent routing strategy) and ELB (explicit load balancing).
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